The New York Yankees star failed a drug test for two anabolic steroids, four sources told the magazine in a story posted yesterday on its Web site.
His name appears on a list of 104 players who tested positive for performance-enhancing drugs in a 2003 baseball survey, SI said. He reportedly tested positive for Primobolan and testosterone while playing for the Rangers.
Rodriguez declined to discuss the tests when approached by SI on Thursday at a gym in Miami, where he lives in the offseason.
"You'll have to talk to the union," he told a reporter. Calls from SI to union head Donald Fehr weren't returned.
Major League Baseball said it was "disturbed" by the report but did not elaborate because of player confidentiality.
"Because the survey testing that took place in 2003 was intended to be nondisciplinary and anonymous, we cannot make any comment on the accuracy of this report as it pertains to the player named," MLB executive vice president Rob Manfred said.
The players union declined to directly address the story's accuracy.
"Information and documents relating to the results of the 2003 MLB testing program are both confidential and under seal by court orders," the union said.
"Anyone with knowledge of such documents who discloses their contents may be in violation of those court orders," the union added.
SI also reported that Rodriguez was tipped off to a drug test in November 2004 by Gene Orza, the players union's chief operating officer.
An e-mail from the Associated Press to Rodriguez's agent, Scott Boras, was not immediately returned. The Yankees and Rangers had no comment.
In a 2007 interview with 60 Minutes, three days after the Mitchell Report was released, Rodriguez denied using peformance-enhancing drugs.
"I've never felt overmatched on the baseball field. ... I felt that if I did ... my work as I've done since I was, you know, a rookie back in Seattle, I didn't have a problem competing at any level," he said.
Rodriguez played for the Rangers in 2003, when he won the American League home run title and MVP award. He was traded to the Yankees in 2004. He is drawing a major league-high $27 million salary after signing a record 10-year, $275 million contract with New York in 2007.
Baseball's drug policy prohibited the use of steroids without a valid prescription since 1991, but there were no penalties for a positive test in 2003.
As part of an agreement with the players union, the testing in 2003 was conducted to determine whether it was necessary to impose mandatory random drug testing across the major leagues in 2004.
The results of the testing of 1,198 players were meant to be anonymous under the agreement between the commissioner's office and the union. SI reported that Rodriguez's testing information was found after federal agents, with search warrants, seized the 2003 results from Comprehensive Drug Testing Inc., in Long Beach, Calif.
That was one of two labs used by baseball in connection with the testing. The seizure in April 2004 was part of the government's investigation into 10 baseball players linked to the BALCO scandal, the magazine reported.
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